I had the tendon pulled back but not detached. My bump was on the back of the heel and he went in from an incision along the outside -- about 3 inches long. Running made mine much worse as the bump ate into the tendon and chewed it up over the years. I had TOPAZ done while he was in there which is a technique to try to heal the tendon. I started this thread
http://www.letsrun.com/forum/flat_read.php?board=1&id=2287689&thread=1726112
when I had the surgery done. It looks like the first couple of pages are no longer there however.
I was in cast for almost 4 weeks, then a boot for a couple of months or so. The recovery was slow but steady.
Other than the JD and grinder, which just might have worked, I really had no options other than surgery -- I don't think I could have even run casually any more with the damage I had done to the tendon.